A magnetic memory cell or device stores information by changing electrical resistance of a magnetic tunnel junction (MTJ) element. The MTJ element typically includes a thin insulating tunnel barrier layer sandwiched between a magnetically fixed layer and a magnetically free layer, forming a magnetic tunnel junction. The magnetization of the free layer can switch between first and second magnetization directions while the magnetization direction of the fixed layer is fixed in the first magnetization direction.
An important aspect of MTJ element is to have high thermal stability and low switching current. However, in conventional MTJ elements, tunnel magnetoresistance (TMR) degrades when exposed to high processing temperatures, such as those employed in back-end-of-line (BEOL) complementary metal oxide semiconductor (CMOS) processing. In other words, conventional MTJ elements have low thermal stability.
In view of the foregoing, it is desirable to provide a MTJ element with improved thermal stability as well as low switching current. Furthermore, it is also desirable to provide a process for forming such MTJ elements which is cost effective and compatible with CMOS processing.